Surgical devices made from glycolide and from p-dioxanone are available commercially in the form of sutures, ligatures, hemostatic clips, surgical staples, and the like. One significant feature of such devices is that they are absorbable in the body, and therefore they eventually disappear from the body after their task has been completed. Representative polymers made from p-dioxanone are described in Doddi et al., U.S. Pat. No. 4,052,988 and representative polymers made from glycolide are described in Schmitt et al., U.S. Pat. No. 3,297,033.
In order to meet specific needs, many different types of polymers containing glycolide and/or p-dioxanone have been proposed. This invention provides block copolymers of glycolide and p-dioxanone that exhibit a high order of initial strength and compliance, but which lose their strength rapidly after implantation in the body. The devices made from the copolymers of the invention, especially sutures, are particularly useful in certain surgical procedures, such as plastic surgery or repair of facial wounds, wherein it is desirable for the device to lose its strength rapidly. One such procedure is known as the "Webster Procedure". It is described in Webster et al., Laryngoscope, Aug. 1976, Vol. 86(8), pages 1280-4, and is a procedure used in plastic surgery or to repair skin lacerations in which a rapidly absorbing suture is used in combination with antitension skin taping. The conventional suturing procedure involved suturing subcutaneous or intradermal tissue with either an absorbable or non-absorbable suture that had to be meticulously removed after two to five days, often with accompanying pain and apprehension. The Webster procedure employs a rapidly absorbing suture so that the implanted portion of the suture will rapidly lose strength, and when the tape is removed a few days later, the external portion of the suture (which, because it was not implanted, did not lose strength) adheres to the tape and is pulled away from the incision. The portion of the suture that was internal, because it loses strength rapidly, breaks and is pulled out with the tape. The pain and discomfort to the patient is much less than when the suture remains intact. Scarring is as good as that resulting from the more usual methods.